The planar microlens is a 2-D integrated microlens fabricated by the selective ion exchange technique. This paper demonstrates a new class of planar microlens which has a high numerical aperture. The new planar microlens uses a swelling structure and index distribution which comes from replacing ions with different ion volumes. Lens diameters from 10 to 400 µm can be fabricated. A numerical aperture larger than 0.5 is achieved when the lens diameter is smaller than 100 µm. Use of this microlens in light coupling between an LD and a single-mode fiber is also evaluated.
© 1990 Optical Society of America
M. Oikawa, H. Nemoto, K. Hamanaka, and E. Okuda, "High numerical aperture planar microlens with swelled structure," Appl. Opt. 29, 4077-4080 (1990)